Labour have accused Stephen Greenhalgh of spinning officer numbers.Boris Johnson’s Deputy Mayor for Policing has been accused of “spinning” and engaging in a “flawed” consultation over police reforms after it emerged published police officer numbers were inaccurate.

The Mayor’s Office for Policing and Crime (MOPAC) is currently consultation on proposals to cut the number of police front counters and free up more officers for front line policing.

On Friday the London Assembly quizzed the Mayor over his proposed 2013/14 budget for the Greater London Authority, including MOPAC and the Metropolitan Police.

During the question and answer session, Labour Assembly Member Joanne McCartney produced a letter from Johnson’s policing deputy in which he admitted police numbers published on City Hall’s London Datastore website were inaccurate.

In his letter, Stephen Greenhalgh accepted that figures for September 2012 “were incorrect” and said that “incomplete” information was provided by the Met “as a result of an MPS restructure.”

Mr Greenhalgh said the Met’s quality assurance procedures had “failed”.

He also conceded that monthly officer figures for October 2009 – September 2011 were wrongly listed as being for May 2009 to April 2011.

Assembly Member McCartney claimed the corrected figures show “there will be over 1,100 fewer police officers in 2015 than Boris has been promising Londoners since January.”

She added: “This mistake means they have either been deliberately misleading Londoners or are so incompetent that they can’t count properly.”

A MOPAC spokesperson later insisted the numbers used for the consultation process “are correct” and were “based on budgeted numbers for police officers in October 2011, looking ahead to 2015.“

The spokesperson added: “The London Datastore is a separate set of figures, that show the actual number of officers working at any one time in the capital. These figures vary according to turnover month by month and it was these figures, which don’t relate to the Police and Crime Plan, that contained some errors when they were uploaded onto the Datastore.

“As the Deputy Mayor explained in his letter, this was a regrettable error and the figures involved have been corrected on the website.”

Following Labour’s publication of his original letter, Mr Greenhalgh wrote to Ms McCartney “to utterly refute” claims that the errors meant the consultation was “flawed”.

Greenhalgh’s letter states: “The letter I sent you…admits to an error on Datastore numbers for SEPTEMBER 2012. These are ENTIRELY UNRELATED to the MPS figures for the Local Policing Model and the public consultation, which relate to a robust OCTOBER 2011 baseline.

“The OCTOBER 2011 figures are not incorrect – and remain a true reflection of the changes proposed and the officers in neighbourhoods and command strengths, on a LIKE FOR LIKE BASIS. The Oct 2011 baseline figure have been adjusted to reflect the services that will continue to be delivered on borough level (i.e. to exclude those services that are being centralised concurrently with the new policing model e.g. crime recording bureau and intelligence bureau).”

In response McCartney accused the Deputy mayor of “giving two different definitions of what his October 2011 figures mean” and claimed MOPAC was “spinning numbers”.

She added: “If Stephen Greenhalgh is correct and the figures given in the MOPAC consultation are accurate, then this means he has been telling Londoners there were fewer police in post than there actually were on the streets – this makes their 2015 target look better than it actually is.

“Alternatively, our original assertion is correct – that they were using an inaccurate baseline for October 2011 – which means the MOPAC consultation is flawed. Either way he is not giving Londoners a clear picture of what is going on. People can ask them which one it is.”